I was getting overshoot on the frame sync when I started a video and I also noticed it would only slow down to match sync even when sync was only just a nudge forwards. As I like control systems I thought I would have a play. The system now syncs very fast from either side of the frame. My crappy motor is making even more noise from the gearbox and the vertical jitter is the gearbox backlash. The new motor should be here soon I hope. I will test it out a bit more and see if it is stable.

That's a pretty fast synch! Your motor is more powerful than mine - mine it teensy, and takes about 10 seconds to get disk fully up to speed. It's impressive to see this happening so quickly, and to perfect frame lock not just speed lock. Your second video appears to be missing/incorrect.

I did modify your post to use [ youtube ] ***** [/youtube ] tags, which embeds the video in the post. You just use the video number at the end of the URL inside the tags *****. Howver, I do not think I broke your link; it did not come up when I used the original URL.

Andrew, thanks for fixing the YouTube links. I will try to do that myself next time. Yes I had one video not listed correctly which should be OK now To be honest the syncing part is the most fun part of this whole project. I still have some occasional start up issues but I am not sure what the cause is, the code seems OK.

The stop button does not work at all for me either. I have not looked into it in detail. It does light up when I press it, I can hold it forever but the video plays on.

A note on your unit/video. The motor is really smooth and quiet but when it grabs sync it gets a noisy tone. I wonder if that is the control system oscillating in place. Until my motor arrives I have to put up with the hideous noise my gearbox makes. It will be interesting to see how the motor audio changes.

I am working on my lens holder and lens shroud now, that should make my unit look a bit more complete too.

PS I am not that keen on the auto play and auto repeat on the non Youtube videos.